Onchocerciasis Elimination Program for the Americas (OEPA)

In the Chicacao area of Guatemala, a child takes a dose of the medication Mectizan to prevent the parasitic disease river blindness. In 2016, Guatemala became the world's fourth nation to receive official verification of elimination of the disease.

The Carter Center's Onchocerciasis Elimination Program for the Americas (OEPA) coordinates the regional initiative to end illness and transmission of onchocerciasis (or river blindness) in the Americas.

Working closely with partners and ministries of health, OEPA has successfully eliminated river blindness transmission from Colombia (2013), Ecuador (2014), Mexico (2015), and Guatemala (2016). Partners include the Pan American Health Organization (PAHO), the U.S. Centers for Disease Control and Prevention, academic institutions, and independent organizations.

As of December 2016, a total of 11 foci of the original 13 endemic areas have eliminated or interrupted transmission as a result of health education and mass drug administration (MDA) with ivermectin (brand name Mectizan®). In 2007 and 2009, Colombia and Ecuador became the first countries in the world to halt river blindness transmission through health education and semiannual distribution of Mectizan, donated by Merck. The countries stopped MDA and entered a 3-year period of post-treatment surveillance (PTS), during which black flies and blood samples from the formerly endemic areas were tested for evidence of onchocerciasis. Mexico and Guatemala both followed suit in 2012, ending mass treatment and entering their PTS period.

In July 2013, Colombia became the first country in the Americas to receive World Health Organization verification of eliminating river blindness. Ecuador, Mexico, and Guatemala each marked their own victories in the campaign to eliminate river blindness, receiving official verification of elimination in 2014, 2015, and 2016, respectively.

The last cases of river blindness in the Americas are limited to the region where the migratory Yanomami live along the Brazil-Venezuela border.

Today, river blindness transmission in the Americas occurs only among the indigenous Yanomami people, who live deep in the Amazon rainforest in an area that straddles the border of Venezuela and Brazil. The two countries have pledged to eliminate the disease from their shared border as soon as possible.

Due to the highly successful efforts of national programs, this once "neglected" tropical disease has been wiped out from 95 percent of the region and no one need fear becoming blind from river blindness in the Americas.

Thanks to these achievements, the Americas region will soon permanently free itself from the threat of this debilitating disease.

At-Risk Populations

Diverse populations and ecosystems are affected by river blindness. In Guatemala and Mexico, the mixed-ancestry and indigenous populations who live on coffee plantations were the most at risk. There, fast-flowing streams providing irrigation to nearby coffee farms acted as breeding grounds for the black flies which spread the disease. The nomadic Yanomami of Brazil and Venezuela are some of the most severely affected groups as their travel throughout the Amazon rainforest places them at continuous risk for exposure.

Achieving Regional Elimination

River blindness is less widespread in the Americas than in Africa. Semiannual treatments — in some cases up to four times annually — with Mectizan over many years can halt disease transmission and improve health by reducing the presence of the parasite's larvae in the human body.

Thousands of community health workers, including these men in Guatemala, have dedicated countless hours to eliminating onchocerciasis in their countries. (All photos: The Carter Center)

Before OEPA started operations in 1993, only 41,911 treatments of Mectizan were administered throughout Latin America, vastly underserving the populations at risk. The Carter Center assumed administrative responsibilities for OEPA in 1996, and twice-per-year treatments began to take off.

After several years of monitoring and evaluation of the program, in 2001, the Carter Center's International Task Force for Disease Eradication, in partnership with the World Health Organization, confirmed that river blindness could be eliminated from the Americas by treating 85 percent or more of infected people with semiannual doses of Mectizan.

Today, the population requiring Mectizan treatment in the Americas has been reduced by more than 95 percent.